Topping valve



FIG. 1 is a back elevational view of the topping valve showing our new design;

FIG. 2 is side perspective view thereof (and since all the sides would like identical, no other sides are views are provided);

FIG. 3 is a front elevational view thereof; and,

FIG. 4 is an exploded view thereof.

It being understood that the inflation device the topping valve would generally be seated within in its environment is shown in broken line merely to indicate its environment and orientation thereto whereby these broken lines are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a topping valve, as shown and described herein. 